Synergy of carbon defect and transition metal on tungsten carbides for boosting the selective cleavage of aryl ether C O bond

Supported transition metal (Mo, W) carbide and nitride catalysts for lignin hydrodeoxygenation: interplay of supports, structure, and catalysis

“…By comparison, W 2 C/CNF was less active than Mo 2 C/CNF in guaiacol HDO with a lower selectivity to the full HDO products such as benzene, toluene and the methoxylated product anisole, even with higher metal loading (Table 1, entries 8 and 9). 31 In addition, Fang et al 45,56,57,67 studied the selective cleavage of C aryl -O bonds over W carbide NPs which are evenly embedded in carbon spheres (CS), including W 2 C@CS, W 1.25 C@CS and WC@CS NPs. W 2 C@CS NPs effectively promoted the C aryl -O bond cleavage, and it was much more active than WC@CS NPs (Table 1, entries 10 and 12).…”

“…For W carbides, the incorporation of Pt species into the initial WC enhances the hydrogenolysis of guaiacol; the guaiacol conversion and phenol yield were apparently increased. 67 With the increased amount of Pt added to WC, guaiacol conversion and phenol selectivity drastically increased, and the phenol space-time yield (STY) reached the maximum value (about 6.5-fold that of WC) when the Pt loading was 1 wt% (Table 3, entries 9-11). However, when the Pt loading was 5%, Pt species covered available C-defect sites, leading to the phenol STY dropping to below that of WC and more benzene ring hydrogenated products produced.…”

Decarboxylation-Induced Defects in MOF-Derived Ni@C Catalysts for Efficient Chemoselective Hydrogenation of Nitrocyclohexane to Cyclohexanone Oxime

“…20−22 Recently, Zong 23 applied a Pd/CFR@HZSM-5 nanocomposite in the hydrodeoxygenation of vanillin with 99% 2-methoxy-4methylphenol yield and found that abundant defects on the carbon surface could stabilize Pd nanoparticles and promote the adsorption of reactants. Additionally, Fang 24 constructed surface carbon defects on a Pt−WC catalyst by incorporation of transition metals and C-etching treatment, and the results showed that carbon defects can boost the adsorption and cleavage of the C−O bond in guaiacol hydrogenation, thus achieving a high yield of phenol.…”

“…In particular, the intrinsic carbon vacancy defects can trap metal atoms and stimulate a strong metal–support interaction (SMSI), thus leading to better dispersion of metal particles and smaller particle size. − Moreover, poorly bonded carbon defects can reduce the splitting of antibonding and bonding orbits, producing electronic states in the band gap, thereby affecting the surface charge states and the adsorption of reactants or key intermediates. − Recently, Zong applied a Pd/CFR@HZSM-5 nanocomposite in the hydrodeoxygenation of vanillin with 99% 2-methoxy-4-methylphenol yield and found that abundant defects on the carbon surface could stabilize Pd nanoparticles and promote the adsorption of reactants. Additionally, Fang constructed surface carbon defects on a Pt–WC catalyst by incorporation of transition metals and C-etching treatment, and the results showed that carbon defects can boost the adsorption and cleavage of the C–O bond in guaiacol hydrogenation, thus achieving a high yield of phenol.…”

Self-Assembled Pt/MoCx/MWCNTs Nano Catalyst for Ethanol Electrooxidation of Fuel Cells

“…Transition metal carbides (TMC) with high metal conductivity, strong corrosion-resistance, high stability and rich sources have a similar catalytic activity to platinum group metals (PGMs) ( Hamo et al, 2019 ; Zhang et al, 2019 ; Jiang et al, 2020 ; Fang et al, 2021 ). They have been widely concerned and applied as catalysts for fuel cells, such as WC ( Hunt et al, 2014 ; Kelly et al, 2014 ; Oh et al, 2014 ), TaC ( Myochi et al, 2018 ; Gao et al, 2020a ), TiC ( Hunt et al, 2016 ), Mo 2 C ( Lin et al, 2017 ; Hassan and Ticianelli, 2018 ).…”